OC 02-04DISTRIBUTION OF CERVICAL SQUAMOUS CELL- AND ADENOCARCINOMA IN SCREEN-DETECTED VERSUS CLINICALLY DETECTED CASES

02. Epidemiology and natural history
H.M.E. Van Agt 1, K. Rozemeijer 1, I.M.C. De Kok 1, S. Naber 1, S.M. Matthijsse 1, E.E.L. Jansen 1, L.I.H. Overbeek 2, A.G. Siebers 2, F.J. Van Kemenade 3, M. Van Ballegooijen 1.
1Erasmus MC, University Medical Center, Department of Public Health, Rotterdam (Netherlands), 2PALGA, the Nationwide network and registry of histo- and cytopathology in the Netherlands, Houten (Netherlands), 3Erasmus MC, University Medical Center, Department of Pathology, Rotterdam (Netherlands)

Background / Objectives

In international studies, the incidence of cervical squamous cell carcinoma has been found to decrease, whereas no changes or even increases were observed in the incidence of cervical adenocarcinoma. It has been suggested that the current screening practices are not sufficient to detect adenocarcinoma precursor lesions. We investigated whether incidence rates of squamous cell carcinoma and adenocarcinoma differ between screen-detected and clinically detected cancers in the Netherlands.


Methods

All cervical cancer cases diagnosed between 1997 and 2007 were included using data from the Dutch nationwide registry of histo- and cytopathology (PALGA) and the Netherlands Cancer Registry. Analyses were restricted to cancers in women aged 29-64 years old, being the ages of the screening program in the Netherlands. Trends in the incidence rates of squamous cell carcinoma and adenocarcinoma were evaluated by calculating the estimated annual percentage change (EAPC). To compare the two sets of trend data, we used a test of parallelism (Joinpoint Trend Analysis).


Results

Overall, screen-detected cancers comprised of 75% squamous cell carcinomas, 17% adenocarcinomas and 8% of other histological types, which was similar to clinically detected cancers (75%, 20% and 6%, respectively; p=0.771). In the period 1997-2007, both screen-detected  squamous cell and adenocarcinoma increased (EAPC =  8.5, 95% CI: 1.4, 16.0; and EAPC = 14.2, 95% CI: 5.2, 23.8, respectively; p=0.014). Clinically detected cancers initially increased during 1997-2002 (EAPC = 26.6, 95% CI: 6.4, 50.0), yet showed a (non-significant) decreasing trend during 2002-2007 (EAPC = -2.4, 95% CI:-12.5, 8.9), a pattern similar to squamous cell and adenocarcinoma (p=0.648).

 


Conclusion

Overall, the distribution of cervical squamous cell and adenocarcinoma  is similar in screen-detected and clinically detected cancers. The trends in the incidence rates of screen-detected and clinically detected cases were similar for both cancer types. The results suggest that the current screening practice in the Netherlands equally detects squamous cell and adenocarcinoma .

 


References